Teleoperation involves operation of a machine at a distance, and is commonly associated with robotics. Early applications were originally intended for manipulation of radioactive, biohazardous, or otherwise inaccessible materials using robotic arms, however in more recent developments they have been used in applications such as robotically-assisted surgery and in space.
A particular variety of teleoperated devices utilize user control of a gripping-type end effector intended to closely approximate the digits of a human hand. Typically these gripping-type end effectors are designed to replicate the hand motion and posture of the controlling operator. Correspondingly, commonly used mechanical human-machine interfaces include a variety of devices worn by the operator, such as exoskeletal mechanical devices, instrumented gloves, motion tracking sensors, or muscular activity sensors. These devices inevitably require direct or close contact with the operator, and as a result may hinder dexterous human motion due to the presence of sensors, attached cables, or other instruments associated with the interface. Other mechanical human-machine interfaces have involved approaches such as dials, joysticks, a computer mouse, or computer graphical interfaces, however these require unnatural operator motions which do not directly translate to the motions of the gripping-type end effector itself. This situation greatly limits the realizable dexterity of the gripping-type end effector, that may be unnatural and must be learned
Natural movements are important elements in using teleoperated equipment if complex and speedy manipulation tasks are to be accomplished, particularly if the manipulation is required to take place in hazardous environments such as hot cells, glove boxes, explosives disarmament, space, and others. It would be advantageous to provide a user interface requiring minimal contact with the operator, in order to allow for a wide working space and range of motions. It would be additionally advantageous if such an interface could operate in a manner that adapts to each specific user through calibration, in order to accommodate the wide range of hand physiologies that might be encountered among differing operators. Such an interface would provide distinct advantages in terms of available dexterity, work space flexibility, and adaptability of different users.
Disclosed here is a user interface for a robotic hand intended to monitor and discern the posture of a user's hand during typical grasping and/or manipulation motions, based on tracking the locations of the user's fingertips relative to some fixed reference point. The user interface substantially anchors a user's palm in a relatively stationary position, and relay various angles of interest to a robotic hand having substantially the same configuration and proportions. The user interface acts to anchor the user's palm in a relatively stationary position and orientation, conducts a calibration procedure to determine the user's applicable physiological dimensions, and determines the angles associated with the metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints of the user's finger necessary to achieve the specific fingertip location. The user interface communicates the respective angles to a gripping-type end effector which will typically closely mimic the user's available range of motion and a typical human proportion.
These and other objects, aspects, and advantages of the present disclosure will become better understood with reference to the accompanying description and claims.